Clean water obtained by desalinating sea water or by purifying wastewater, constitutes a major technological objective in the so-called water century. In this work, a high-performance reverse osmosis (RO) composite thin membrane using multi-walled carbon nanotubes (MWCNT) and aromatic polyamide (PA), was successfully prepared by interfacial polymerization. The effect of MWCNT on the chlorine resistance, antifouling and desalination performances of the nanocomposite membranes were studied. We found that a suitable amount of MWCNT in PA, 15.5 wt.%, not only improves the membrane performance in terms of flow and antifouling, but also inhibits the chlorine degradation on these membranes. Therefore, the present results clearly establish a solid foundation towards more efficient large-scale water desalination and other water treatment processes.

No abstract

Carbon nanotubes/polyamide (PA) nanocomposite thin films have become very attractive as reverse osmosis (RO) membranes. In this work, we used molecular dynamics to simulate the influence of single walled carbon nanotubes (SWCNTs) in the polyamide molecular structure as a model case of a carbon nanotubes/polyamide nanocomposite RO membrane. It was found that the addition of SWCNTs decreases the pore size of the composite membrane and increases the Na and Cl ion rejection. Analysis of the radial distribution function of water confined in the pores of the membranes shows that SWCNT+PA nanocomposite membranes also exhibit smaller clusters of water molecules within the membrane, thus suggesting a dense membrane structure (SWCNT+PA composite membranes were 3.9% denser than bare PA). The results provide new insights into the fabrication of novel membranes reinforced with tubular structures for enhanced desalination performance.

No abstract

We prepared poly(styrene-b-butadiene-b-styrene) (SBS) matrix composites in which multiwalled carbon nanotubes (MWCNTs) were homogeneously dispersed, and their morphologies, thermal properties, and mechanical properties were investigated. The incorporation of MWCNTs into the SBS matrices improved their thermal and mechanical properties with appropriate flexibility. The MWCNT/SBS composites did not flow above 100 °C, and showed surprising improvements in terms of their creep properties. The results indicated the possibility of broadening their use in high temperature applications, and of significantly improving permanent strain, which are currently the main demerits of TPE. These drastic improvements in the various properties of MWCNT/SBS composites were assumed to have been caused by the formation of a three-dimensional structure at the interfacial phase of the SBS matrix along the MWCNTs, which we designated as a “cell structure”.